1. Field of the Invention
The present invention generally relates to virtual microscopy and more particularly relates to retrieval, manipulation, and viewing of three dimensional image objects from three dimensional virtual microscope slide (“3D digital slide”) images.
2. Related Art
Conventional microscopes, using mechanical focusing mechanisms of sufficient quality, are easily focused by an observer. The feedback loop between the eye/brain and the fingers is extremely rapid and accurate. If any part of the feedback loop is impaired, however, the process of obtaining perfect focus becomes extremely difficult, time consuming and even inaccurate. These impairments may arise from poor optical quality, insufficient or incorrect illumination, inaccuracies in the focusing mechanism, or even due to poor visual acuity of the operator.
More recently, conventional computer implemented microscope systems have provided the ability to remotely access high resolution images of microscope slides for a number of years. Devices capable of creating such images fall into two broad categories: (1) remote controlled (or robotic) microscopes; and (2) imagers, which create some type of electronic or photographic image of some, or all, of the specimen. Each type has its advantages and disadvantages, many of which are unique to the particular application.
Conventional imaging systems are capable of creating large enough images to capture an entire specimen at moderate or high magnification. These images are called virtual microscope slides or virtual slides. Because of their extremely large size, virtual slides are usually limited to a single focus level (“z-plane”). Many types of microscope specimens are very thin so a single z-plane virtual slide is sufficient. Other types of microscope specimens, however, are thicker than the depth of field of the objective lens.
Recent improvements in imaging systems include the ability to create virtual slides with multiple z-planes. These virtual slide images are called three dimensional (“3D”) virtual slides and include imagery data from multiple focus levels throughout the thickness of the microscope specimen. What is needed is a system and method for extracting three dimensional image objects from the image data in a three dimensional virtual slide for viewing by a user.